diff --git a/src/unlocker/main.cpp b/src/unlocker/main.cpp
index 2c3676b..4ff889b 100644
--- a/src/unlocker/main.cpp
+++ b/src/unlocker/main.cpp
@@ -71,6 +71,21 @@ void StartWatchdog()
 
 bool run()
 {
+    /*
+        mutex check before running
+    */
+    HANDLE mtx = CreateMutexA(NULL, TRUE, "Global\\HexUnlocked");
+    if (mtx == NULL) return false;
+    if (GetLastError() == ERROR_ALREADY_EXISTS)
+    {
+        MessageBoxA(NULL, "Program is already running", "Hex: Unlocked", MB_OK | MB_ICONERROR | MB_ICONINFORMATION);
+        CloseHandle(mtx);
+        return false;
+    }
+
+    /*
+        init
+    */
     seallib::Logger mainLog("Main");
     mainLog.addSink(std::make_shared<ConOutSink>());